Avodah Zarah, Daf Samekh Het, Part 4
Introduction
Today s section analyzes the baraita from above concerning various prohibited substances that fall into a mixture. I am copying here the three clauses of the baraita:
1) If terumah yeast and ordinary yeast fell into dough, each being sufficient to cause leavening, and they leavened it, it is prohibited; but R. Shimon permits it.
2) If the terumah yeast fell in first, all agree that it is prohibited. But if the ordinary yeast fell in first and then the terumah yeast or yeast from mixed plantings in a vineyard, it is prohibited. But R. Shimon permits it.
3) If [nesekh] wine fell into lentils or [nesekh] vinegar into split beans, it is prohibited, but R. Shimon permits it.
הני תלתא בבי דקתני למה לי בשלמא בבא דסיפא קמ"ל בפוגם מעיקרא מחלוקת מציעתא נמי השביח ולבסוף פגם דברי הכל אסור
These three clauses which are taught, do I need them all?
The last clause makes sense because it teaches us that if the [forbidden substance] worsens the taste from the outset, they still disagree.
The middle clause also [needs to be taught so that we know] if it improved and in the end deteriorated all agree that it is prohibited.
The second clause teaches the principle that if the substance worsens the taste (vinegar fell into cold beans) from the outset the tannaim still disagree. R. Shimon permits and R. Meir prohibits.
The second clause teaches that if the taste is first improved (by the first yeast being put in) and then worsens (when too much yeast is put in) the mixture is prohibited and even R. Shimon agrees.
אלא רישא למה לי השתא ומה סיפא דלא קא משבח כלל אסרי רבנן רישא דקא משבח מיבעיא
But why do I need the first clause? Since in the third clause, where it does not improve it at all, the rabbis still prohibit it, how much more so [must they prohibit it] where it does improve it.
If in the final clause where the vinegar only worsens the taste the rabbis (R. Meir) prohibit, obviously they would in the first clause where the leavening agent at first improves the flavor and then worsens it. So why do we need this first clause?
אמר אביי רישא לר"ש אצטריך והכי קאמרי ליה רבנן לר"ש עיסה זו ראויה להחמיץ בשתי שעות מי גרם לה שתחמיץ בשעה אחת איסור ור’ שמעון כשהשביחו שניהם השביחו כשפגמו שניהם פגמו
Abaye said: The first clause is necessary for R. Shimon, and thus the Rabbis said to R. Shimon: This dough should take two hours to leaven and what caused it to leaven in one hour? Prohibited [yeast]. And R. Shimon [how would he respond]?
When there was improvement, both [kinds of yeast] improved it and when there was deterioration, both worsened it.
Abaye points out that we do need the first clause in order to learn that R. Shimon permits this mixture. The rabbis say that it was the prohibited yeast they caused the dough to ferment faster. Therefore, although it went bad eventually, it was the prohibited yeast that improved the dough. R. Shimon would say that we should not look at it this way. The two doughs together helped improve at the beginning and the two doughs together made it worse at the end. The fact that the prohibited dough aided in the deterioration means that the mixture should be permitted.
לר"ש ליצטרף היתר ואיסור בהדי הדדי וליתסר
ר"ש לטעמיה דאמר אפי’ איסור ואיסור נמי לא מיצטרפי דתנן הערלה וכלאי הכרם מצטרפין ר"ש אומר אין מצטרפין
But according to R. Shimon, the permitted and prohibited elements should be combined and render [the dough] prohibited!
R. Shimon follows his own opinion, that even two prohibited substances do not combine, for we have learned: Orlah and mixed plantings combine; R. Shimon says that they do not combine.
The Talmud invokes another principle which would explain why the mixture should be prohibited. When two elements fall into a mixture, one prohibited and one permitted, in this case the terumah yeast and the ordinary yeast, and neither is sufficient to achieve the intended result (leavening) they can combine together to achieve the result and therefore the mixture is prohibited. R. Shimon, who looks at the initial leavening as if it was performed by half the ordinary yeast and half the forbidden yeast should say the two combine to create a prohibition.
He does not because R. Shimon does not hold that different substances combine, even if both a prohibited. For instance if some orlah and mixed plantings fell into a mixture and neither alone was sufficient to prohibit the mixture R. Shimon would hold that the mixture is permitted.